gibbs



COURTNEY CONOVER, OF PHILADELPHIA, PENNSYLV a SAN FRANCISCO, CALIFORNIA.

PROCESS FOR THE MANUFACTURE OF No Drawing.

Specification of Letters Patent.

AND HARRY D. GIBBS, OE

Y reunions.

Patented May 6, 1919,

Application filed-June v, 1917. semi narrates.

(FILED UNDER, THE AGT 0! CH 3, 1383, 22 STAT. In, 625.)

To all whom it may concern:

Be it known that we, COURTNEY Conovnn and HARRY D. GIBBS, citizens of the United States of America, and emplo cos of the Department of Agriculture, residing in. the city of Philadelphia, county of Philadelphia, State of Pennsylvania, and in the city of San Francisco, county of San Francisco, State of California, respectively, (whose post-office address is Washington, D. (1,) have invented a new and useful Process for the Manufacture of Anthtraquinone.

This application is made under the act of March 3, 1888, chapter 143 (22 Stat, 625), and the invention herein described and claimed may be used by the Government of the United States or any of its officers or emplo ees in the prosecution of work for the overnment, or any person in the United States, without payment to us of any royalty.

@ur invention relates to a process for the manufacture of anthraquinone from anthracene.

lit is well known that anthraquinone is commonly produced by the oxidation of anthracene in an extremely fine state of division by means of chromic acid, In this process the reduction of the anthracene to the iinestate of division is difficult and ex pensive, and further the chromic acid subsequently used for oxidation is a costly reagent. The object of our invention is to provide a process for the manufacture of anthraquinone which will be free from the objectionable features of the processes emplo ed at present.

(liar invention consists in the production of anthraquinone from anthracene by heating the anthraceneuntil it passes into the vapor phase, mixing this anthracene vapor with an oxygen-containing gas mixture, fore-- ing this mixture of gases into close contact with finely divided oxids of the metals of the sixth group of the periodic system via: chromium, molybdenum, tungsten, an uranium, heated to a-temperature ranging from 250 C. to 650 (3., under which treatment the anthracene is partially oxidized to form thevaluable product named. v

To illustrate the practical operation of our process we shall describe in ,detail the preferred procedure. Anthracene is melted chamber the gas mixture is forced into close.

contact with oxids of a metal of the sixth group of the periodic system (preferably oxide of molybdenum) in the form of a fine powder. This powder is supported on trays or on a porous material where, by mechanical means, the current of mixed gases is forced through it. The gases are kept under pressure only suflicient to cause them to flow continuously through the reaction chamber.- The products of the reaction, together with unchanged anthracene, are condensed, and the anthraquinone is separated from the unchanged anthracene and other substances, if any, by well-known processes.

We have discovered that the process as above described may be varied in many ways and yet will produce anthraquinone. Thus, oxygen may be substituted Wholly or in part for air, or air may be mixed with a gas which is relatively inert under the conditions obtaining in the process. The

oxide of the metals of the sixth group of the periodic system, viz: chromium, molybdenum, tungsten, and uranium, may be mixed. with or combined with each other or with other substances, such as other metallic oxide, or with asbestos, pumice stone, or other materials. The gas mixture may be brought in contact with or forced through the catalyst in many did'erent ways. The proportion of anthracene vapor to the oxygen-con.

taining gas mixture may be varied within" .1

wide limits. cene, together with the substances commonly associated with it may be used instead of pure an-thracene. And the reaction products may be separated by various wellknown means,

Having thus descri our invention, we claim-- 1. A process for the manufacture of anthraquinone, which process consists in sub- Materials containing anthrajecting anthracene in the gaseous state and mixed with an oxygen-containing gas mixture, to the action of oxids of a metal of the sixth group of the periodic system heated to temperatures ranging from 350 to 550 centigrade. v

2. A process for the manufacture of anthraquinone, which process consists in subjecting anthracene in the gaseous state and mixed with atmosphere air to the action of oxids of a metal of the sixth group of the periodic system heated to temperatures ranging from 350 to 550 centigrade.

3. A process for the manufacture of anthraquinone, which process consists in subjecting anthracene in the gaseous state and mixed with an oxygen-containing gas mixture, to the action of oxids of a metal of the sixthgroup of the periodic system heated to temperatures ranging from 250 to 650 centigrade.

4. A process for the manufacture of anthraquinone, which process consists in subjecting, while in the gaseous state and mixed with an oxygen-containing gas mixture, anthracene, together with other substances derived from coal-tar, to the action of oxide of a metal of the sixth group of the periodic system heated to temperatures ranging from 250 to 650 centigrade.

In testimony whereof We aifix our signatures in the presence of two subscribing wit- DGSSGS.

COURTNEY CON OVER. HARRY D. GIBBS. Witnesses:

PHILIP L. GowEN, R. R. WILLIAMS. 

